Doppler shift oscillations of hot solar coronal plasma seen by SUMER: A signature of loop oscillations?

被引:205
作者
Wang, TJ [1 ]
Solanki, SK [1 ]
Curdt, W [1 ]
Innes, DE [1 ]
Dammasch, IE [1 ]
机构
[1] Max Planck Inst Aeron, D-37191 Katlenburg Lindau, Germany
关键词
Sun : corona; Sun : flares; Sun : UV radiation; Sun; X-rays; gamma rays;
D O I
10.1086/342189
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We report observations of strongly damped Doppler shift oscillations detected in a flare line, Fe XIX, with the Solar Ultraviolet Measurement of Emitted Radiation spectrometer. Spectra were recorded above an active region at the western limb of the Sun, from lines with formation temperatures ranging from 0.01 to 10 MK. However, the oscillations were seen only in the hot plasma (>6 MK) lines. The Doppler oscillations have periods of 14-18 minutes, with an exponential decay time of 12-19 minutes, and show an initial large blueshift pulse with peak velocities up to 77 km s(-1). Several indications suggest that the Doppler oscillations are incompressible coronal loop oscillations that are excited impulsively by a flarelike event that also produced a strong increase in Fe XIX emission.
引用
收藏
页码:L101 / L104
页数:4
相关论文
共 22 条
[1]   THEORY OF RADIO PULSATIONS IN CORONAL LOOPS [J].
ASCHWANDEN, MJ .
SOLAR PHYSICS, 1987, 111 (01) :113-136
[2]   Coronal loop oscillations observed with the Transition region and Coronal explorer [J].
Aschwanden, MJ ;
Fletcher, L ;
Schrijver, CJ ;
Alexander, D .
ASTROPHYSICAL JOURNAL, 1999, 520 (02) :880-894
[3]   Transverse oscillations in coronal loops observed with TRACE - II. Measurements of geometric and physical parameters [J].
Aschwanden, MJ ;
De Pontieu, B ;
Schrijver, CJ ;
Title, AM .
SOLAR PHYSICS, 2002, 206 (01) :99-132
[4]   Active region EUV transient brightenings - First results by EIT of SOHO JOP 80 [J].
Berghmans, D ;
Clette, F .
SOLAR PHYSICS, 1999, 186 (1-2) :207-229
[5]  
EDWIN PM, 1983, SOL PHYS, V88, P179, DOI 10.1007/BF00196186
[6]   High-temperature lines in SUMER spectra recorded above a bright solar active region [J].
Feldman, U ;
Curdt, W ;
Doschek, GA ;
Schühle, U ;
Wilhelm, K ;
Lemaire, P .
ASTROPHYSICAL JOURNAL, 1998, 503 (01) :467-474
[7]   Identification of spectral lines in the 500-1600 Å wavelength range of highly ionized Ne, Na, Mg, Ar, K, Ca, Ti, Cr, Mn, Fe, Co, and Ni emitted by flares (Te ≥ 3 x 106 K) and their potential use in plasma diagnostics [J].
Feldman, U ;
Curdt, W ;
Landi, E ;
Wilhelm, K .
ASTROPHYSICAL JOURNAL, 2000, 544 (01) :508-521
[8]   Large Doppler shifts in X-ray plasma: An explosive start to coronal mass ejection [J].
Innes, DE ;
Curdt, W ;
Schwenn, R ;
Solanki, S ;
Stenborg, G ;
McKenzie, DE .
ASTROPHYSICAL JOURNAL, 2001, 549 (02) :L249-L252
[9]   Correlated dynamics of hot and cool plasmas in the main phase of a solar flare [J].
Kliem, B ;
Dammasch, IE ;
Curdt, W ;
Wilhelm, K .
ASTROPHYSICAL JOURNAL, 2002, 568 (01) :L61-L65
[10]   HIGH-RESOLUTION PHOTOGRAPHY OF THE SOLAR CHROMOSPHERE .17. GEOMETRY OF H-ALPHA FLARE LOOPS OBSERVED ON THE DISK [J].
LOUGHHEAD, RE ;
WANG, JL ;
BLOWS, G .
ASTROPHYSICAL JOURNAL, 1983, 274 (02) :883-&